Merge branch 'jc/checkout-m-twoway' into maint
[git] / builtin / diff-tree.c
1 #include "cache.h"
2 #include "diff.h"
3 #include "commit.h"
4 #include "log-tree.h"
5 #include "builtin.h"
6 #include "submodule.h"
7
8 static struct rev_info log_tree_opt;
9
10 static int diff_tree_commit_sha1(const unsigned char *sha1)
11 {
12         struct commit *commit = lookup_commit_reference(sha1);
13         if (!commit)
14                 return -1;
15         return log_tree_commit(&log_tree_opt, commit);
16 }
17
18 /* Diff one or more commits. */
19 static int stdin_diff_commit(struct commit *commit, char *line, int len)
20 {
21         unsigned char sha1[20];
22         if (isspace(line[40]) && !get_sha1_hex(line+41, sha1)) {
23                 /* Graft the fake parents locally to the commit */
24                 int pos = 41;
25                 struct commit_list **pptr, *parents;
26
27                 /* Free the real parent list */
28                 for (parents = commit->parents; parents; ) {
29                         struct commit_list *tmp = parents->next;
30                         free(parents);
31                         parents = tmp;
32                 }
33                 commit->parents = NULL;
34                 pptr = &(commit->parents);
35                 while (line[pos] && !get_sha1_hex(line + pos, sha1)) {
36                         struct commit *parent = lookup_commit(sha1);
37                         if (parent) {
38                                 pptr = &commit_list_insert(parent, pptr)->next;
39                         }
40                         pos += 41;
41                 }
42         }
43         return log_tree_commit(&log_tree_opt, commit);
44 }
45
46 /* Diff two trees. */
47 static int stdin_diff_trees(struct tree *tree1, char *line, int len)
48 {
49         unsigned char sha1[20];
50         struct tree *tree2;
51         if (len != 82 || !isspace(line[40]) || get_sha1_hex(line + 41, sha1))
52                 return error("Need exactly two trees, separated by a space");
53         tree2 = lookup_tree(sha1);
54         if (!tree2 || parse_tree(tree2))
55                 return -1;
56         printf("%s %s\n", sha1_to_hex(tree1->object.sha1),
57                           sha1_to_hex(tree2->object.sha1));
58         diff_tree_sha1(tree1->object.sha1, tree2->object.sha1,
59                        "", &log_tree_opt.diffopt);
60         log_tree_diff_flush(&log_tree_opt);
61         return 0;
62 }
63
64 static int diff_tree_stdin(char *line)
65 {
66         int len = strlen(line);
67         unsigned char sha1[20];
68         struct object *obj;
69
70         if (!len || line[len-1] != '\n')
71                 return -1;
72         line[len-1] = 0;
73         if (get_sha1_hex(line, sha1))
74                 return -1;
75         obj = lookup_unknown_object(sha1);
76         if (!obj || !obj->parsed)
77                 obj = parse_object(sha1);
78         if (!obj)
79                 return -1;
80         if (obj->type == OBJ_COMMIT)
81                 return stdin_diff_commit((struct commit *)obj, line, len);
82         if (obj->type == OBJ_TREE)
83                 return stdin_diff_trees((struct tree *)obj, line, len);
84         error("Object %s is a %s, not a commit or tree",
85               sha1_to_hex(sha1), typename(obj->type));
86         return -1;
87 }
88
89 static const char diff_tree_usage[] =
90 "git diff-tree [--stdin] [-m] [-c] [--cc] [-s] [-v] [--pretty] [-t] [-r] [--root] "
91 "[<common diff options>] <tree-ish> [<tree-ish>] [<path>...]\n"
92 "  -r            diff recursively\n"
93 "  --root        include the initial commit as diff against /dev/null\n"
94 COMMON_DIFF_OPTIONS_HELP;
95
96 static void diff_tree_tweak_rev(struct rev_info *rev, struct setup_revision_opt *opt)
97 {
98         if (!rev->diffopt.output_format) {
99                 if (rev->dense_combined_merges)
100                         rev->diffopt.output_format = DIFF_FORMAT_PATCH;
101                 else
102                         rev->diffopt.output_format = DIFF_FORMAT_RAW;
103         }
104 }
105
106 int cmd_diff_tree(int argc, const char **argv, const char *prefix)
107 {
108         int nr_sha1;
109         char line[1000];
110         struct object *tree1, *tree2;
111         static struct rev_info *opt = &log_tree_opt;
112         struct setup_revision_opt s_r_opt;
113         int read_stdin = 0;
114
115         init_revisions(opt, prefix);
116         gitmodules_config();
117         git_config(git_diff_basic_config, NULL); /* no "diff" UI options */
118         opt->abbrev = 0;
119         opt->diff = 1;
120         opt->disable_stdin = 1;
121         memset(&s_r_opt, 0, sizeof(s_r_opt));
122         s_r_opt.tweak = diff_tree_tweak_rev;
123         argc = setup_revisions(argc, argv, opt, &s_r_opt);
124
125         while (--argc > 0) {
126                 const char *arg = *++argv;
127
128                 if (!strcmp(arg, "--stdin")) {
129                         read_stdin = 1;
130                         continue;
131                 }
132                 usage(diff_tree_usage);
133         }
134
135         /*
136          * NOTE! We expect "a ^b" to be equal to "a..b", so we
137          * reverse the order of the objects if the second one
138          * is marked UNINTERESTING.
139          */
140         nr_sha1 = opt->pending.nr;
141         switch (nr_sha1) {
142         case 0:
143                 if (!read_stdin)
144                         usage(diff_tree_usage);
145                 break;
146         case 1:
147                 tree1 = opt->pending.objects[0].item;
148                 diff_tree_commit_sha1(tree1->sha1);
149                 break;
150         case 2:
151                 tree1 = opt->pending.objects[0].item;
152                 tree2 = opt->pending.objects[1].item;
153                 if (tree2->flags & UNINTERESTING) {
154                         struct object *tmp = tree2;
155                         tree2 = tree1;
156                         tree1 = tmp;
157                 }
158                 diff_tree_sha1(tree1->sha1,
159                                tree2->sha1,
160                                "", &opt->diffopt);
161                 log_tree_diff_flush(opt);
162                 break;
163         }
164
165         if (read_stdin) {
166                 int saved_nrl = 0;
167                 int saved_dcctc = 0;
168
169                 if (opt->diffopt.detect_rename)
170                         opt->diffopt.setup |= (DIFF_SETUP_USE_SIZE_CACHE |
171                                                DIFF_SETUP_USE_CACHE);
172                 while (fgets(line, sizeof(line), stdin)) {
173                         unsigned char sha1[20];
174
175                         if (get_sha1_hex(line, sha1)) {
176                                 fputs(line, stdout);
177                                 fflush(stdout);
178                         }
179                         else {
180                                 diff_tree_stdin(line);
181                                 if (saved_nrl < opt->diffopt.needed_rename_limit)
182                                         saved_nrl = opt->diffopt.needed_rename_limit;
183                                 if (opt->diffopt.degraded_cc_to_c)
184                                         saved_dcctc = 1;
185                         }
186                 }
187                 opt->diffopt.degraded_cc_to_c = saved_dcctc;
188                 opt->diffopt.needed_rename_limit = saved_nrl;
189         }
190
191         return diff_result_code(&opt->diffopt, 0);
192 }